Why does chronic hyperextension at the knee joint increase the risk of anterior cruciate ligament (ACL) injury during rapid deceleration?

💡 Explanation

Chronic hyperextension alters the normal joint biomechanics, causing increased stress on the ACL, especially during deceleration. Because the ACL is a primary restraint to anterior tibial translation, altered biomechanics makes it vulnerable. Therefore, ACL injury risk increases, rather than a simple muscle imbalance or collagen defect.

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